1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) 2023, Linaro Limited
4 */
5
6 #include <linux/module.h>
7 #include <linux/platform_device.h>
8 #include <linux/regulator/consumer.h>
9 #include <linux/regmap.h>
10 #include <linux/of.h>
11 #include <linux/phy/phy.h>
12
13 /* eUSB2 status registers */
14 #define EUSB2_RPTR_STATUS 0x08
15 #define RPTR_OK BIT(7)
16
17 /* eUSB2 control registers */
18 #define EUSB2_EN_CTL1 0x46
19 #define EUSB2_RPTR_EN BIT(7)
20
21 #define EUSB2_FORCE_EN_5 0xe8
22 #define F_CLK_19P2M_EN BIT(6)
23
24 #define EUSB2_FORCE_VAL_5 0xeD
25 #define V_CLK_19P2M_EN BIT(6)
26
27 #define EUSB2_TUNE_USB2_CROSSOVER 0x50
28 #define EUSB2_TUNE_IUSB2 0x51
29 #define EUSB2_TUNE_RES_FSDIF 0x52
30 #define EUSB2_TUNE_HSDISC 0x53
31 #define EUSB2_TUNE_SQUELCH_U 0x54
32 #define EUSB2_TUNE_USB2_SLEW 0x55
33 #define EUSB2_TUNE_USB2_EQU 0x56
34 #define EUSB2_TUNE_USB2_PREEM 0x57
35 #define EUSB2_TUNE_USB2_HS_COMP_CUR 0x58
36 #define EUSB2_TUNE_EUSB_SLEW 0x59
37 #define EUSB2_TUNE_EUSB_EQU 0x5A
38 #define EUSB2_TUNE_EUSB_HS_COMP_CUR 0x5B
39
40 struct eusb2_repeater_init_tbl_reg {
41 unsigned int reg;
42 unsigned int value;
43 };
44
45 struct eusb2_repeater_cfg {
46 const struct eusb2_repeater_init_tbl_reg *init_tbl;
47 int init_tbl_num;
48 const char * const *vreg_list;
49 int num_vregs;
50 };
51
52 struct eusb2_repeater {
53 struct device *dev;
54 struct regmap *regmap;
55 struct phy *phy;
56 struct regulator_bulk_data *vregs;
57 const struct eusb2_repeater_cfg *cfg;
58 u32 base;
59 enum phy_mode mode;
60 };
61
62 static const char * const pm8550b_vreg_l[] = {
63 "vdd18", "vdd3",
64 };
65
66 static const struct eusb2_repeater_init_tbl_reg pm8550b_init_tbl[] = {
67 { EUSB2_TUNE_IUSB2, 0x8 },
68 { EUSB2_TUNE_SQUELCH_U, 0x3 },
69 { EUSB2_TUNE_USB2_PREEM, 0x5 },
70 };
71
72 static const struct eusb2_repeater_init_tbl_reg smb2360_init_tbl[] = {
73 { EUSB2_TUNE_IUSB2, 0x5 },
74 { EUSB2_TUNE_SQUELCH_U, 0x3 },
75 { EUSB2_TUNE_USB2_PREEM, 0x2 },
76 };
77
78 static const struct eusb2_repeater_cfg pm8550b_eusb2_cfg = {
79 .init_tbl = pm8550b_init_tbl,
80 .init_tbl_num = ARRAY_SIZE(pm8550b_init_tbl),
81 .vreg_list = pm8550b_vreg_l,
82 .num_vregs = ARRAY_SIZE(pm8550b_vreg_l),
83 };
84
85 static const struct eusb2_repeater_cfg pmiv0104_eusb2_cfg = {
86 /* No PMIC-specific init sequence, only board level tuning via DT */
87 .init_tbl = (struct eusb2_repeater_init_tbl_reg[]) {},
88 .init_tbl_num = 0,
89 .vreg_list = pm8550b_vreg_l,
90 .num_vregs = ARRAY_SIZE(pm8550b_vreg_l),
91 };
92
93 static const struct eusb2_repeater_cfg smb2360_eusb2_cfg = {
94 .init_tbl = smb2360_init_tbl,
95 .init_tbl_num = ARRAY_SIZE(smb2360_init_tbl),
96 .vreg_list = pm8550b_vreg_l,
97 .num_vregs = ARRAY_SIZE(pm8550b_vreg_l),
98 };
99
eusb2_repeater_init_vregs(struct eusb2_repeater * rptr)100 static int eusb2_repeater_init_vregs(struct eusb2_repeater *rptr)
101 {
102 int num = rptr->cfg->num_vregs;
103 struct device *dev = rptr->dev;
104 int i;
105
106 rptr->vregs = devm_kcalloc(dev, num, sizeof(*rptr->vregs), GFP_KERNEL);
107 if (!rptr->vregs)
108 return -ENOMEM;
109
110 for (i = 0; i < num; i++)
111 rptr->vregs[i].supply = rptr->cfg->vreg_list[i];
112
113 return devm_regulator_bulk_get(dev, num, rptr->vregs);
114 }
115
eusb2_repeater_init(struct phy * phy)116 static int eusb2_repeater_init(struct phy *phy)
117 {
118 struct eusb2_repeater *rptr = phy_get_drvdata(phy);
119 struct device_node *np = rptr->dev->of_node;
120 struct regmap *regmap = rptr->regmap;
121 u32 base = rptr->base;
122 u32 poll_val;
123 int ret;
124 u8 val;
125
126 ret = regulator_bulk_enable(rptr->cfg->num_vregs, rptr->vregs);
127 if (ret)
128 return ret;
129
130 regmap_write(regmap, base + EUSB2_EN_CTL1, EUSB2_RPTR_EN);
131
132 /* Write registers from init table */
133 for (int i = 0; i < rptr->cfg->init_tbl_num; i++)
134 regmap_write(regmap, base + rptr->cfg->init_tbl[i].reg,
135 rptr->cfg->init_tbl[i].value);
136
137 /* Override registers from devicetree values */
138 if (!of_property_read_u8(np, "qcom,tune-usb2-preem", &val))
139 regmap_write(regmap, base + EUSB2_TUNE_USB2_PREEM, val);
140
141 if (!of_property_read_u8(np, "qcom,tune-usb2-disc-thres", &val))
142 regmap_write(regmap, base + EUSB2_TUNE_HSDISC, val);
143
144 if (!of_property_read_u8(np, "qcom,tune-usb2-amplitude", &val))
145 regmap_write(regmap, base + EUSB2_TUNE_IUSB2, val);
146
147 if (!of_property_read_u8(np, "qcom,tune-res-fsdif", &val))
148 regmap_write(regmap, base + EUSB2_TUNE_RES_FSDIF, val);
149
150 /* Wait for status OK */
151 ret = regmap_read_poll_timeout(regmap, base + EUSB2_RPTR_STATUS, poll_val,
152 poll_val & RPTR_OK, 10, 5);
153 if (ret)
154 dev_err(rptr->dev, "initialization timed-out\n");
155
156 return ret;
157 }
158
eusb2_repeater_set_mode(struct phy * phy,enum phy_mode mode,int submode)159 static int eusb2_repeater_set_mode(struct phy *phy,
160 enum phy_mode mode, int submode)
161 {
162 struct eusb2_repeater *rptr = phy_get_drvdata(phy);
163 struct regmap *regmap = rptr->regmap;
164 u32 base = rptr->base;
165
166 switch (mode) {
167 case PHY_MODE_USB_HOST:
168 /*
169 * CM.Lx is prohibited when repeater is already into Lx state as
170 * per eUSB 1.2 Spec. Below implement software workaround until
171 * PHY and controller is fixing seen observation.
172 */
173 regmap_write(regmap, base + EUSB2_FORCE_EN_5, F_CLK_19P2M_EN);
174 regmap_write(regmap, base + EUSB2_FORCE_VAL_5, V_CLK_19P2M_EN);
175 break;
176 case PHY_MODE_USB_DEVICE:
177 /*
178 * In device mode clear host mode related workaround as there
179 * is no repeater reset available, and enable/disable of
180 * repeater doesn't clear previous value due to shared
181 * regulators (say host <-> device mode switch).
182 */
183 regmap_write(regmap, base + EUSB2_FORCE_EN_5, 0);
184 regmap_write(regmap, base + EUSB2_FORCE_VAL_5, 0);
185 break;
186 default:
187 return -EINVAL;
188 }
189
190 return 0;
191 }
192
eusb2_repeater_exit(struct phy * phy)193 static int eusb2_repeater_exit(struct phy *phy)
194 {
195 struct eusb2_repeater *rptr = phy_get_drvdata(phy);
196
197 return regulator_bulk_disable(rptr->cfg->num_vregs, rptr->vregs);
198 }
199
200 static const struct phy_ops eusb2_repeater_ops = {
201 .init = eusb2_repeater_init,
202 .exit = eusb2_repeater_exit,
203 .set_mode = eusb2_repeater_set_mode,
204 .owner = THIS_MODULE,
205 };
206
eusb2_repeater_probe(struct platform_device * pdev)207 static int eusb2_repeater_probe(struct platform_device *pdev)
208 {
209 struct eusb2_repeater *rptr;
210 struct device *dev = &pdev->dev;
211 struct phy_provider *phy_provider;
212 struct device_node *np = dev->of_node;
213 u32 res;
214 int ret;
215
216 rptr = devm_kzalloc(dev, sizeof(*rptr), GFP_KERNEL);
217 if (!rptr)
218 return -ENOMEM;
219
220 rptr->dev = dev;
221 dev_set_drvdata(dev, rptr);
222
223 rptr->cfg = of_device_get_match_data(dev);
224 if (!rptr->cfg)
225 return -EINVAL;
226
227 rptr->regmap = dev_get_regmap(dev->parent, NULL);
228 if (!rptr->regmap)
229 return -ENODEV;
230
231 ret = of_property_read_u32(np, "reg", &res);
232 if (ret < 0)
233 return ret;
234
235 rptr->base = res;
236
237 ret = eusb2_repeater_init_vregs(rptr);
238 if (ret < 0) {
239 dev_err(dev, "unable to get supplies\n");
240 return ret;
241 }
242
243 rptr->phy = devm_phy_create(dev, np, &eusb2_repeater_ops);
244 if (IS_ERR(rptr->phy)) {
245 dev_err(dev, "failed to create PHY: %d\n", ret);
246 return PTR_ERR(rptr->phy);
247 }
248
249 phy_set_drvdata(rptr->phy, rptr);
250
251 phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
252 if (IS_ERR(phy_provider))
253 return PTR_ERR(phy_provider);
254
255 return 0;
256 }
257
eusb2_repeater_remove(struct platform_device * pdev)258 static void eusb2_repeater_remove(struct platform_device *pdev)
259 {
260 struct eusb2_repeater *rptr = platform_get_drvdata(pdev);
261
262 if (!rptr)
263 return;
264
265 eusb2_repeater_exit(rptr->phy);
266 }
267
268 static const struct of_device_id eusb2_repeater_of_match_table[] = {
269 {
270 .compatible = "qcom,pm8550b-eusb2-repeater",
271 .data = &pm8550b_eusb2_cfg,
272 },
273 {
274 .compatible = "qcom,pmiv0104-eusb2-repeater",
275 .data = &pmiv0104_eusb2_cfg,
276 },
277 {
278 .compatible = "qcom,smb2360-eusb2-repeater",
279 .data = &smb2360_eusb2_cfg,
280 },
281 { },
282 };
283 MODULE_DEVICE_TABLE(of, eusb2_repeater_of_match_table);
284
285 static struct platform_driver eusb2_repeater_driver = {
286 .probe = eusb2_repeater_probe,
287 .remove = eusb2_repeater_remove,
288 .driver = {
289 .name = "qcom-eusb2-repeater",
290 .of_match_table = eusb2_repeater_of_match_table,
291 },
292 };
293
294 module_platform_driver(eusb2_repeater_driver);
295
296 MODULE_DESCRIPTION("Qualcomm PMIC eUSB2 Repeater driver");
297 MODULE_LICENSE("GPL");
298